Fix #170

Author: zetachang

CHANGELOG.md

@@ -26,6 +26,7 @@ Whitespace conventions:
 
 ### Fixed
 
+- `Element#render` trigger unnecessary re-mounts when called multiple times. (#170)
 - Gets rid of react warnings about updating state during render (#155)
 - Multiple HAML classes (i.e. div.foo.bar) was not working (regression introduced in 0.8.8)
 - Don't send nil (null) to form components as the value string (#157)

lib/react/top_level.rb

@@ -119,10 +119,14 @@ def self.[](selector)
   end
 
   define_method :render do |container = nil, params = {}, &block|
-    klass = Class.new(React::Component::Base)
+    if `#{self.to_n}._reactrb_component_class === undefined`
+      `#{self.to_n}._reactrb_component_class = #{Class.new(React::Component::Base)}`
+    end
+    klass = `#{self.to_n}._reactrb_component_class`
     klass.class_eval do
       render(container, params, &block)
     end
-    React.render(React.create_element(klass), self)
+    
+    React.render(React.create_element(`#{self.to_n}._reactrb_component_class`), self)
   end
 end if Object.const_defined?('Element')

spec/react/opal_jquery_extensions_spec.rb

@@ -6,6 +6,27 @@
     React::API.clear_component_class_cache
   end
 
+  it 'will reuse the wrapper componet class for the same Element' do
+    stub_const 'Foo', Class.new(React::Component::Base)
+    Foo.class_eval do
+      param :name
+      def render
+        "hello #{params.name}"
+      end
+
+      def component_will_unmount
+
+      end
+    end
+
+    expect_any_instance_of(Foo).to_not receive(:component_will_unmount)
+
+    test_div = Element.new(:div)
+    test_div.render { Foo(name: 'fred') }
+    test_div.render { Foo(name: 'freddy') }
+    expect(Element[test_div].find('span').html).to eq('hello freddy')
+  end
+
   it 'renders a top level component using render with a block' do
     stub_const 'Foo', Class.new(React::Component::Base)
     Foo.class_eval do